code: def kilometers(meters=0, miles=0, feet=0, nautical=0):
      """
      Convert distance to kilometers.
      """
      ret = 0.0
      if meters:
          ret += meters / 1000.0
      if feet:
          ret += feet / ft(1.0)
      if nautical:
          ret += nautical / nm(1.0)
      ret += miles * 1.609344
      return ret
  
file_path: geopy/geopy/units.py
imports: import math
label_desc: Use image node_id 5 for calling a global function with example usage: kilometers(meters, miles, feet, nautical) and returns: ret